ALSO using all coins I get to unlock more Hard stages (most efficient way of getting more tokens without doing the 'Free Tokens' offers (which rarely work), or buying token packs). Then waiting for my 10 free tokens to refill, and completing ALL THESE STAGES AT ONCE, watching ads to add +10 tokens whenever the opportunity comes up, saving all those tokens, and spending them to unlock MORE stages, lather, rinse, repeating.
god but it's taking forever